1. Field of the Invention
The present invention generally relates to a scheduling method, in particular, to a system, method, and recording medium for scheduling packets to be transmitted.
2. Description of Related Art
The wide application of Internet and wireless communication has increasing demands for multi-media services via Internet and mobile/wireless channel streaming media. In an Internet protocol (IP) network, multi-media is provided by a server and streamed to one or more wired or wireless clients. Wired connection includes dial-up, integrated services digital network (ISDN), cable, digital subscriber line protocol (referred to collectively as “xDSL”), optical fiber, local area network (LAN), wide area network (WAN), and so on. Electronic equipments employing wireless communication include phones (for example, cell-phones), personal data assistants (PDAs), and hand-held, portable computers, and so on.
Worldwide Interoperability for Microwave Access (WiMAX) is a new wireless broadband network system based on IEEE 802.16 standards. The communication between a WiMAX base station and a subscriber station is achieved by sending/receiving a series of frames.
WiMAX 802.16e system is mobile, and may be used in a variety of transmission environments. Besides, the WiMAX 802.16e system has many different types of support services, and the support services have different requirements on quality of service (QoS). Therefore, a conventional method for scheduling packets to be transmitted may neither meet the requirements on QoS nor achieve the optimal transmission performance. Further, for real-time services such as VoIP and streaming services, the delay bounds thereof are defined in the system specification. However, for non-real-time services, only the minimum reserved traffic rates thereof are defined in the specification. As a result, the conventional method for scheduling packets to be transmitted is impossible to effectively support non-real-time services. Therefore, it is required to develop a method for transmitting packets to improve the performance and capacity of the system while keeping the QoS thereof in a mixed service (real-time service and non-real-time service) environment.